Journal cover Journal topic
Natural Hazards and Earth System Sciences An interactive open-access journal of the European Geosciences Union
doi:10.5194/nhess-2016-334
© Author(s) 2016. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
01 Nov 2016
Review status
A revision of this discussion paper was accepted for the journal Natural Hazards and Earth System Sciences (NHESS) and is expected to appear here in due course.
On the Resonance Hypothesis of Tsunami and Storm Surge Runup
Nazmi Postacioglu1, M. Sinan Özeren2, and Umut Canlı1 1Istanbul Technical University, Department of Physics, Maslak 34469 Istanbul, Turkey
2Istanbul Technical University, Eurasia Institute of Earth Sciences, Maslak 34469 Istanbul, Turkey
Abstract. Resonance has recently been proposed as the fundamental underlying mechanism that shapes the amplification in coastal runup for both Tsunamis and storm surges. It is without doubt that the resonance plays a rôle in runup phenomena of various kinds, however we think that the extent at which it plays its role has not been completely understood. For incident waves, the best approach to investigate the rôle played by the resonance would be to calculate the normal modes by taking radiation damping into account and then test how those modes are excited by the incident waves. There are a small number of previous works that attempt to calculate the resonant frequencies but they do not relate the amplitudes of the normal modes to those of the incident wave. This is because, by not including radiation damping, they automatically induce a resonance that leads to infinite amplitudes, thus preventing them from predicting the exact contribution of the resonance to coastal runup. In this study we consider two different coastal geometries: an infinitely wide beach with a constant slope connecting to a flat-bottomed deep ocean and a bay with sloping bottom, again, connected to a deep ocean. For the fully 1-D problem we find significant resonance if the bathymetric discontinuity is large. For the 2-D ocean case the analysis shows that the wave confinement is very effective when the bay is narrow. The bay aspect-ratio is the determining factor for the radiation damping.

Citation: Postacioglu, N., Özeren, M. S., and Canlı, U.: On the Resonance Hypothesis of Tsunami and Storm Surge Runup, Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-334, in review, 2016.
Nazmi Postacioglu et al.
Nazmi Postacioglu et al.

Viewed

Total article views: 307 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
227 64 16 307 7 17

Views and downloads (calculated since 01 Nov 2016)

Cumulative views and downloads (calculated since 01 Nov 2016)

Viewed (geographical distribution)

Total article views: 307 (including HTML, PDF, and XML)

Thereof 305 with geography defined and 2 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 29 May 2017
Publications Copernicus
Download
Short summary
Tsunami waves and some other water waves such as storm surges get amplified as they approach the coast due to shoaling. The underlying physics is energy conservation but there are several aspects of this phenomenon that are still active research topics. Resonance is one. As waves reflect from the coast, resonance can hinder the efficiency of the reflection by trapping some of the energy in the coastal region. We investigate this phenomenon by taking the bathymetry and bay shape into account.
Tsunami waves and some other water waves such as storm surges get amplified as they approach the...
Share